A 2026 guide to GST return filing — GSTR-1, GSTR-3B, GSTR-9, the QRMP scheme, monthly and quarterly due dates, the new 3-year filing limit, late fees and interest. Check GST return due dates for 2026 including GSTR-1, GSTR-3B, CMP-08 and GSTR-4. Learn filing frequency, late fees, interest and penalties in simple language. Stay updated with the GST calendar 2026-27. Check all GST due dates, return filing deadlines, and compliance schedules for businesses and taxpayers in India. GST return filing Due Dates vary by return type and filing frequency, making it essential to maintain a well-structured compliance calendar for FY 2025-26. What are the GST Return Filing Due Dates 2026 in India? The GST return calendar 2026 covers multiple return types applicable to different categories of taxpayers. 1 How GST filing frequency works in 2026 15 changes in 2026 that every GST-registered business must act on 2.0.1 1. 3-year return filing hard block (effective December 2025) 2.0.2 2. E-invoicing threshold lowered to ₹5 crore 2.0.3 3. Invoice Management System (IMS) fully active from 2026 2.0.4 4. New GSTR-1A form for supplier amendments 2.0.5 5. Timely GST return filing is one of the most basic yet frequently missed compliance obligations for registered taxpayers in India. Missing a due date attracts late fees and interest, blocks input tax credit for your buyers, and can even lead to suspension of your GST registration. This article sets out the important GST return due dates for 2026, covering monthly, quarterly (QRMP), composition and annual returns, along with a ready compliance calendar. Who files which GST return The return. July 14, 2026 13 min read Updated: July 14, 2026 The Monthly GST Cycle at a Glance Every GST Return, Frequency and Due Date Monthly Filing vs QRMP: Which Cycle Are You On? Composition Dealers: CMP-08 and GSTR-4 Annual Returns: GSTR-9 and GSTR-9C Late Fees and Interest Practical Tips to Stay on Schedule Share Complete 2026 reference for every GST return — GSTR-1, GSTR-3B, CMP-08, GSTR-4, GSTR-9, GSTR-9C, plus GSTR-5/6/7/8/10. Who files what, frequency, exact due dates with primary-source citations, QRMP scheme breakdown, Cat A vs Cat B state lists, and the FY 2024-25 changes — including the Rs. 2 Cr GSTR-9 exemption (Notification 15/2025-CT), GSTR-9C self-certification, GSTR-1A amendment form, and IMS impact on non-editable GSTR-3B. Monthly & quarterly GST due dates for GSTR-1, GSTR-3B, GSTR-9, and CMP-08 for FY 2026-27 with late fee calculation.